1. Field of the Invention
The present invention relates to a signal processing device and a projection display apparatus, which convert an image input signal into an image output signal.
2. Description of the Related Art
Heretofore, there has been known a display device configured to display images captured with an imaging device such as a camera. Solid-state light sources (for example, laser diodes (LDs) or light-emitting diodes (LEDs)) having a wide color reproduction range have been developed as light sources for illuminating such a display device. Here, there may be a case where a color reproduction range of the display device is different from that of the imaging device.
To handle such a case, a technique (for example, Japanese Patent Publication No. 2000-324350) has been proposed for reducing a color reproduction range of an input device (for example, an imaging device) when the color reproduction range of an input device gets wider than that of an output device (for example, a display device). Specifically, a direction to reduce the color reproduction range is changed for each hue to produce a natural-looking image.
On the other hand, consider a case where a color reproduction range of an output device (for example, a display device) gets wider than that of an input device (for example, an imaging device). In such a case, when the output device displays an image according to an image input signal inputted from the input device, color coordinates of the image result is wider than those of an actual object. Note that the color coordinates are defined by saturation and hue.